Despite any pre-conceived notions to the contrary, cardboard is a fairly resilient material and can actually be great material for shelving, if you don't plan to store anything too heavy on the shelves. Whether money is tight or you just want to carry out a great little do-it-yourself project, building a cardboard shelf is an excellent way to add new shelving space to your home or living area. First, you will need to track down the actual cardboard. Feel free to use old cardboard boxes or pick some up from your local liquor store. Now, you will also need a hot glue gun, duct tape, a utility knife, and some material to place over your shelves. You can either plan to paint the shelves afterward or use some type of fabric to add some style.
For each shelf, plan to use roughly three regular sized boxes. Use your utility knife to cut off the top four flaps of each box. Then use your duct tape across the outer creases of the cardboard to add stability to each individual box. Place three boxes next to one another so that the open ends are facing toward you and use your hot glue gun to glue the three boxes together in a straight row. You can now stand the boxes vertical or sideways and you should have ample shelving space. Also, feel free to add additional boxes if you would like more space. Depending on the type of wall you'll be hooking up to, light brackets or nails with plastic washers should suffice in hanging the shelves. Remember to use extra duct tape on the creases to strengthen your box and try to avoid placing anything too heavy on the shelves.